Defense Secretary Robert Gates acknowledged it will be “tough” to close the US prison at Guantanamo Bay by a January deadline set by President Barack Obama.

“It’s going to be tough” for the Obama administration to meet the January 22 deadline to shut the camp condemned as a “legal black hole” by rights groups, Gates said.

But played down the importance of missing the deadline, saying he had supported setting the date as a way of pushing progress toward closing Guantanamo Bay, the US military prison in southern Cuba where 223 “war on terror” detainees remain.

“I actually was one of those who said we should (set a deadline) because I know enough from being around this town that if you don’t put a deadline on something, you’ll never move the bureaucracy,” Gates told ABC television’s “This Week” in an interview.